Vented mold for castings



Ml E Sept. 24, 1929. F. H. MQREHEAD l VENTED MOLD FOR CASTINGS Filed July 3. 1926 Patented Sept. 24, 1929 UNITED STATES PATENT OFFICE FRENCH H. MOREHEAD, OF BOSTON, MASSACHUSETTS, AISSIGN'OR OF ONEHALF TO FREDERICK C. LANGENBERG, OF WATIERTOIILI,` MASSACHUSETTS VENTED MOLD FOR `CASTINGS Y Application filed July 3, 1926. serial No. 120,268.

My invention relates to molds for producing small castings and particularly to socalled permanent molds which are themselves made of metal and are used for successive casting operations. The mold embodying the present invention is intended for use with the casting machine shown in the application for Letters Patenty of the United States filed November 28, 1925, Serial No.`

71,927. For use in machines of this char acter, the mold is conveniently made in two parts which are closed while the metal is being poured and are then opened to permit the casting to be ejected, the successive operations being performed as rapidly as possible. Molds of this kind, are preferably watercooled, and each mold contains a plurality of mold pockets each of which produces a casting. In molds of this kind each of the pockets for the several castings must be vented to permit the escape of air and gases from each pocket, and this has been a matter of great difficulty because the entire faces of two halves of the mold have bee-n in contact with each other over the entire parting plane. Therefore it has been necessary to drill holes through the mold at locations where they will not pierce the water jackets, or to form long circuitous grooves in the contacting faces of the parts of the mold. These requirements have interfered seriously with the design of the mold and have added materially to the expense of construction.

My present invention overcomes the difficulties and makes it possible to provide a multiple pocket permanent mold having a considerable number of pockets with proper vents and with a minimum of labor.

Fig. 1 is an edge view of the mold embodying my invention.

Fig. 2 is a face view of one of the proximate faces of the halves of the mold shown in Fig 1.

Fig. 3 is a section on line 3 3, Fig. 2.

Fig. 4 shows the casting to be produced.

Fig. 5 shows the core which is employed.

In the drawings the halves of the mold are designated 11 and 12. The parting plane, i. e. the plane of the contacting faces is indicated by the line 9--9 in Fig. 1. At

13, 14, 15, 16, 17, 18, l,19 and 20 are shown pockets, each of which produces a casting. The shape of the castingwill be seen in Fig. 4t and the shape of the corewill be seen in Figu. Around each ofthe pockets 13 to 2() inclusive and preferablyon the proximate faces of both halves 11 and 12- of the mold are ribs 21. y The ribs 21 on the half 11 cooperate with the lcorresponding ribs on the half 12, and together close the A pockets and prevent the escape vof any metal. The area 22 surrounding the pockets and outside the ribs is below the surface of the ribs as seen in Fig. 3where the surface of the'ribs is shown at 21. halves of the mold are closedtheA opposing ribs Contact with each other so that a'space When the two 23 (see Fig. 1) is left between the two halves l of the mold. Similar ribs 4241 outline 'the'inlet passageways 25 which leadl from thevfunnel shaped'main passage 26 to theseveral pockets. All the' unoccupied area on the proximate faces of the two halves ofthe mold is below, the surface of the ribs andis separated from the passageways 25l and26 by ribs as described. v

It will be understood of course that these l passageways I.are laid out of a proper size and inclination so that themolten metal will flow through all the pockets and fill them completely.

Wherever required vents 27 are formed to permit the escape of air and gases from the pockets and passageways. These vents are convenienty formed by cutting or filing a shallow groove transversely of one of the ribs so that when the halves of the mold are in Contact with each other there is formed a passage, the inner end of which connects the space intended to contain the molten metal with the space 22 between the proximate faces of the plates. Since even such enclosed space as the one marked 30 in Fig. 2 is open to the atmosphere through the passage 31, the adjacent pockets can be vented by cutting grooves directly across the ribs to the space between the proximate faces of the halves of the mold. In the drawings, I have shown a cooling space for water or other cooling medium in the back of the mold at 34. It will be understood of course that the water jacket is arranged according to the shape or the thickness of the casting and the cooling requirements. It will also be seen that since the vents communicate entirely with the space between thevproximate halves of the mold, the vents do not interfere with the cooling jackets and a simple and economical structure lis provided. The vents are of such size that they permit the escape of the gas but do not permit the escape of metal. When constructed as preferred with grooves in the faces of the ribs, the vents clear themselves of metal each time the mold is opened.

Having thus described my invention, I claim:

1. A multiple pocket mold comprising a plurality of parts each containing a plufrality of cooperating pockets of a shape complementary to the shape of the article to bel produced, each of said pockets being surrounded by a rib raised above the surface of the proximate yfaces of the parts of the moldand being vented by a passage transverse to said rib and leading from the pocket to the space between the proximate faces of the mold'on the exterior of'said rib.

2. The multiple pocket mold comprisingv two parts which are spaced apart from each other by ribs surrounding each of the mold pockets, said pockets being vented through the ribs to the space outside the ribs between 35i the'halves of the mold.

.parts which are lspaced apart from each 3. The multiple,v pocket mold comprising other by ribs `surrounding each of the mold pockets, said ribs being grooved on their faces to form a vent from a metal receiving portion to the space outside the ribs and between the halves of the mold.

In testimony whereof I aix my signature.

FRENCH H. MOREHEAD. 

